Electric fuse



E. L. MASON ELECTRIC FUSE Apl il 9, 1940.

Filed July 9, 1938 2 Sheets-Sheet 1 Inventor .22 .22. .ZI'asoaz v By and A itomeys April 9, 1940.

E. L. MASON 2,196,638

ELECTRIC FUSE Filid July 9, 19I 58 2 Sheets-Sheet 2 A iiomeys Patented Apr. 9, 1940 UNITED, STATES PATENT OFFICE ELECTRIC FUSE 9 Elmer L. Mason, Barnesville, Ohio Application July 9, 1938, Serial No. 218,404

2 Claims. (01. 200-431) This invention relates to electric fuses and particularly to that type of fuse known as the knifeblade contact type; and an object of the invention is, generally, to improve upon electric fuses of this character.

The invention together with its objects and advantages will be best understood from a study of the following description taken in connection with the accompanying drawings wherein:

Figure l is a view partly in section and partly in elevation showing the improved fuse,

Figure 2 is an elevational view of the fuse with parts broken away and shown in section,

Figure 3 is a view partly in section and partly in elevation of the fuse links and terminals therefor,

Figure 4 is an end elevational view of the fuse,

Figure 5 is an elevational view of the cover plate of the fuse casing,

Figure 6 is an elevational view of the fuse casing with the cover plate removed,

Figure 7 is a fragmentary detail sectional view illustrating a slightly modified form of the invention, and

Figure 8 is an end elevational view of the form of the invention shown in Figure 7.

Figure 9 is a detail view partly in section and partly in elevation showing an alternate manner of connecting a fuse link with its terminals.

Referring to the drawings by reference numerals it will be seen that in accordance with the invention the fuse per se consists of a pair of terminals 5 and 6 connected by a fuse link I of any desired type.

For connecting the fuse link I with its terminals 5 and 6 the terminals, as shown in Figure 3, are provided at one end with sockets II which receive the ends of the link I. Threadedly engaged with one wall of the socket are clamping screws I2 which at their inner ends are provided with enlarged disk-like heads that serve to clamp the fuse link at the ends thereof between the heads of the screws and the walls of the sockets I I opposite to the walls of the sockets with which the screws I2 are threadedly engaged.

In the form of the invention suggested in Figure 9 the link I is connected at each end thereof with a terminal, only one of which, 5, is shown in Figure 9, through the medium of a U-shaped member 9 that straddles one wall of the socket 8 of the terminal, the end of the link 'I being clamped between one leg of the member 9 and a wall of the socket through the medium of a screw III that threads through the outer leg of the U-shaped member 9, the wall of the socket 8 straddled by the U-shaped member, and at its inner end has bearing engagement with the inner leg of the U-shaped member 9 as shown in said Figure 9.

Also, in accordance with the present invention 8 there is provided a suitable casing for the fuse, and in both forms of the invention the casing indicated generally by the reference numeral I3 consists of an elongated hollow block of insulating material. The hollow block I3 provides an elongated open front chamber I4 therein and is constructed and arranged with a pair of laterally spaced parallelribs I3 in the rear of said chamber extending longitudinally from end to end of the block and forming therebetween an open front central channel I5 enlarged at its ends, as at I5 and I6, so that said channel is wider and deeper at said ends thereof. The shallower and narrower intermediate portion of said channel I5 accommodates the link 'I therein and the ends I5 and I6 the sockets II of the terminals 5 and 6,

respectively. A pair of slots I6 is provided in the ends 22 of the block I3, respectively, in the longitudinal center thereof, said slots being narrower than the ends I5 and I6 and opening onto the front of the casing to snugly receive the terminals 5 and 6, respectively.

The casing I3 is closed at its front through the medium of a removable cover plate I8 of suitable insulation material.

The cover plate I8, as best shown in Figures 5 and 6, is of rectangular panel form to fit the open front of the casing I3 and is provided with a beveled edge, as at I8, fitting against a similar internal beveled edge I3" on said casing I3, a shoulder I8" extending around the same for engagement with a complemental shoulder I3"' extending around said edge I3" of casing I3, and a rib I9 fitting into the open front of said casing. The rib I9 is longitudinally concave, as best shown in Figure 2, and at each end thereof is bifurcated to provide in the longitudinal center thereof a pair of end grooves I9, whereby said rib is adapted at the ends thereof to straddle the sockets II and terminals 5, 6, while the central part of said rib arches away from the link I out of contact therewith. At the outer ends of the grooves I9 said edge I8 of the-cover plate I8 has extending therefrom a pair of short key ribs l9 adapted to fit into the outer ends of the slots I6 as best shown in Figure 4.

At one end thereof the rib I9 is provided with a pair of integral teats 20 that are adapted to spring into openings ZI provided in one end 22. of the casing I3 while at the opposite end thereof the rib 19 has suitably anchored thereto one end of spring latches 23 that are accommodated in recesses 24 provided therefor in said end of the rib. The spring latches 23 are provided with integral teats 25 adapted to spring into engagement with openings 26 provided in the opposite end of the casing, all of which is clearly shown in Figure 2.

At the spring-latch equipped end thereof the cover plate I8 is provided with a lip 28 adapted to be engaged by ac finger in a manner to facilitate removal of the cover plate.

It will thus be seen that I have provided an cficient casing of simple construction and design. With this casing, when a fuse burns out the cover plate It is quickly and easily removed and a new fuse readily inserted therein after which the cover plate is again fastened in position.

It will be noted that in the form of the invention shown in Figures 1. to 4 inclusive the ends 22, 7;"! thereof are integral with the body of the casing.

In the form of the invention shown in Figures 7 and 8, instead of having the end walls integral with the body of the casing, the casing at the opposite end thereof is open as at 29 and 30 respectively. Arranged within the openings 29 and 3S metallic end plates 3!, 32 and the plates are su tably slotted as at to accommodate the terminals 5 and 6.

Also to accommodate the plates 3|, 32 the casing is provided adjacent the ends 29, 39 thereof with internal grooves 33 which accommodate the edges of the plates as shown.

Also as shown each of the plates 3|, 32 is provided at opposite sides of the slot therein with openings 34- to accommodate the latch teats carried by the cover plate for releasably securing the cover plate in position on the case.

It is thought that a clear understanding of the construction utility and advantages of an electric fuse embodying the features of the present invention will be had without a more detailed description.

Having thus described the invention what is claimed as new is:

1. In a device of the class described, a pair of fuse terminals having an enlarged end socket, respectively, a fiat fuse link secured at its opposite ends in said sockets, respectively, for connecting said terminals together, and a junction box for housing said sockets and link comprising an elongated hollow block having an open front for the insertion of said sockets and link therein, and slotted ends for straddling said terminals beyond said sockets, said block having therein in the rear thereof a pair of laterally spaced ribs extending longitudinally from end to end thereof and constructed and arranged to form therebetween an open front channel having enlarged ends for accommodating said sockets and a restricted intermediate portion for accommodating said link, and a detachable closure plate for the front of said block.

2. In a device of the class described, a pair of fuse terminals having an enlarged end socket, respectively, a fiat fuse link secured at its opposite ends in said sockets, respectively, for connecting said terminals together, and a junction box for housing said sockets and link comprising an elongated hollow block having an open front for the insertion of said sockets and link therein, and slotted ends for straddling said terminals beyond said sockets, said block having therein in the rear thereof a pair of laterally spaced ribs extending longitudinally from end to end thereof and constructed and arranged to form therebetween an open front channel having enlarged ends for accommodating said sockets and a restricted intermediate portion for accommodating said link, and a detachable closure plate for the front of said block comprising a longitudinal rib fitting into said front, said rib being longitudinally concaved to clear the link intermediate the sockets and bifurcated at the ends thereof to straddle said sockets, respectively, and thereby function to maintain the same in a common plane.

ELMER L. MASON. 

